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1、制冷空调专业英语,Unit One,Lesson 1 Air Lesson 2 The Need of Conditioning Lesson 3 The Cleaning of Air Lesson 4 Thermal Storage,New Words & Expressions Text Notes to the Text Exercise,Lesson 3 The Cleaning of Air,Lesson 3,New Words & Expressions,（医）过敏的, 患过敏症的,granular adj.,由小粒而成的, 粒状的,fiber n.=fibre,光纤,suspe
2、nd vt.,吊, 悬挂;v.延缓,organism n.,生物体, 有机体,mold n.,霉菌,spore n.;vi.,孢子长孢子,bacteria n.,细菌,bacteria-free adj.,无菌的,pollen n.; vt.,花粉,传授花粉给,allergic adj.,Lesson 3,New Words & Expressions:,atmosphere n.,大气, 空气, 气氛,atmospheric adj.,大气的,magnitude n.,大小, 数量, 巨大,量级,furnishings n.,家具,设备, 服饰用品,discolor v.,使脱色, 使污染,
3、filter n.;vt.,n.滤波器, 过滤器, 筛选； vt.过滤, 渗透, 用过滤法除去,radioactive adj.,放射性的, 有辐射能,disorder n. ;vt.,n.杂乱, 混乱, 无秩序状态; vt.扰乱, 使失调, 使紊乱,Lesson 3,New Words & Expressions:,播送, 发射, 传动, 传送, 传输, 转播,allergen n.,变态反应原, 过敏原,characteristic adj.; n.,adj.特有的, 表示特性的, 典型的; n.特性, 特征,velocity n.,速度, 速率, 迅速, 周转率,remove vt.,移
4、动, 开除, 移交,distinguish v.,区别, 辨别,transmission n.,Text,Lesson 3,Atmospheric dust is a complex mixture of smoke, mists, fumes, dry granular particles, and fibers suspended in air. In addition air may contain living organisms such as mold spores, bacteria, and plant pollens that may cause diseases or al
5、lergic responses.,大气中的尘埃是由烟、雾、汽、干燥的粒状微粒以及在空气里悬浮的纤维等复杂的东西混合而成的。此外，空气中可能包含类似霉菌孢子、细菌、植物花粉之类的有机体，而这些有可能引起疾病或过敏反应。,Particles in the atmosphere range in size from less than 10-6 up to the order of magnitude of the dimension of leaves and insects1. The particles exist in all sizes and shapes and generally
6、it is impossible to design one air cleaner that is best for all applications,这些微粒的尺寸，小的数量级达到10-6，大的达到树叶和昆虫的尺寸。微粒的大小和形状各式各样，一般不可能设计一种能很好地适用所有场合的空气净化器。,Lesson 3,Text:,Different degrees of air cleanliness are required for various applications. Another consideration is the fact that dust particles in th
7、e air may damage the conditioned spaces or its furnishings. For example, the walls may be discolored if even the smallest components of the atmospheric dust are not removed.,不同的应用场合需要不同型号的空气净化装置。另外，还要考虑到空气中的尘粒会损害空调空间和其内的家具。例如，即使残留尘粒的最小组分也有可能使墙壁褪色。,Lesson 3,Text:,Unfortunately the smallest particles
8、cause the most discoloring. Therefore, in this case, electronic air cleaners or high performance dry filters are required. In clean room applications or when radioactive particles are present, extremely high performance filters should be employed.,不幸的是，尘粒越小墙壁褪色越严重。因此，在这种情况下，需要使用电子空气净化器或高性能干燥过滤器。在绝对无
9、尘室或存在放射性微粒时，需要利用极高性能的过滤器。,Lesson 3,Text:,One of the most effective ways of controlling allergic disorders is to remove the allergens from the air by using high performance filters.2 Of all the characteristics affecting the performance of an air filter, particle size is the most important; however, t
10、he cleaning efficiency of a filter is affected to some extent by the velocity of the air stream.,控制由于过敏造成的身体紊乱最有效方法之一，是使用高性能过滤器除掉空气中的过敏源。微粒大小是所有的特征中影响空气过滤器的性能最主要的因素；然而，在某种程度上净化器的净化效率受气流流速的影响。,Lesson 3,Text:,The major factor influencing filter design and selection is the degree of air cleanliness req
11、uired. In general the cost of the filter or filter system will increase as the size of the particles to be removed decreases. Maintenance will also increase in the same way.,影响过滤器设计和选择的主要因素是所需要的空气洁净等级。通常过滤器或过滤器系统的成本随着去除尘粒尺寸的减小而增加，维护费用也将相应地增加。,Lesson 3,Text:,There are three operating characteristics
12、that distinguish the various types of air cleaners. These are the efficiency, the air flow resistance, the dust-holding capacity3. Efficiency measures the ability of the air cleaner to remove particulate matter from an air stream and the average efficiency over the life of the filter is the most mea
13、ningful for most applications.4,可以通过3个运行特性来区分空气洁净器的不同类型，这就是效率、空气流动阻力、尘容量。效率衡量洁净器从空气气流中除去颗粒物质的能力，在过滤器的使用寿命期内，平均效率对大多数设备起到决定性作用。,Lesson 3,Text:,The air flow resistance is the loss in total pressure across the filter at a given air flow rate. This of course is a very important consideration. The dust-h
14、olding capacity defines the amount of a particular type of dust an air cleaner can hold while operating at a specific airflow rate and maximum airflow resistance.,空气流动阻力是在给定空气流量的 条件下通过过滤器的总压力的损失。这 是一个很重要的需要考虑的因素。尘容 量是指在特定的空气流量和最大的气流 阻力条件下运行时，空气洁净器能容纳 的特殊类型尘粒的数量。,Lesson 3,Text:,Sometimes the dust-hol
15、ding capacity refers to the value attained before the filter efficiency is seriously reduced. Therefore, to have a complete rating of an air cleaner, data should be made available on efficiency, resistance, and dust-holding capacity. The effect of the dust loading on the efficiency and resistance is
16、 also important.,有时尘容量指的是在过滤器效率下降前所达到容纳量。因此，只有得到空气洁净器的效率、空气流动阻力、尘容量的数据，才能给出一个完整的评估。灰尘的负载对效率和阻力的影响也是重要的。,Lesson 3,Text:,In general, however, the graveimetric efficiency of a filter gives the ratio of the mass of the dust arrested by the filter to the total mass of the dust fed to the filter. The second type of efficiency is called the dust spot efficiency. This is designed to rate filters for their ability to prevent discoloration.,然而，一般说来，过滤器的测重法效率反映出过滤器所捕集到的尘量与通过过滤器的总尘量的比率。第二种类型的效率是污点效率，用来评估过滤器
